JRO if the sea conditions permit, and by that I mean if the bar is not breaking really badly, Big River can provide shelter in a pinch but difficult to get into. Sufficient water for a few miles up stream, no services, watch for old pilings from logging shows from years ago. You would need to get in before any sea was running, perhaps just after daylight which would mean leaving Humboldt Bay at night. Getting out of there is tough across the bar which keeps moving around. If I were you and had decided to do the passage, I would wait in Eureka for at least a 24 hour weather window and give the points a wide berth overnight to make Bodega Bay.
Additionally, don't try to enter Grays Harbor at night without local knowledge... make sure you leave Neah Bay early enough to get there in daylight. I've been in there several times and once I aborted heading north and just stood off shore until daybreak as the approach can be be foul and confusing even with good charts. That was in the day before chart plotters, however. If fuel capacity is a problem, purchase a small bladder at Fisherman's Supply in Seattle and fill it before leaving. Make sure it is lashed down securely before venturing out past Cape Flattery.
I still like John A's suggestion of trucking her down... Capt Phil

We trucked our catamaran last of Oct last year north to the Columbia River and cost about $5000.00 from San Diago. We would have sailed but going north into strong head winds was not our sort of fun and we wanted to save our new-to-us catamaran for future cruses. Going south is easier I hear but expect strong north to northwest breezes and in a Carver you should expect the exaust to be blowing into the boat and cockpit some so get new batteries for your O2 monitors, it'll feel like seasickness

you may not need your engines running down hill--i didnt use mine much after ensenada, and only used it then as we were caught by the calm at salsipuedes, just north of ensenada. there should be plenty of wind and decent seas at this time of year.
downhill is EASY ... uphill is where the bash comes in. unless you get the headwinds that like to play with folks, no matter which direction ye head....

I do highly recommend stoping by Two Harbor on Catalina Island the 14-15 of Oct for the Lattitude's and Attitudes' Crusers party. It's put on by the Port Royal Yacht club and Bob Bitchen and crew host it. The food was the greatest Prime rib and the suba guy's brought fresh lobster and after dinner there was .25% left over they were trying to give away. The band was Eric Stone with my friends Steve and wife Shelly backing him up, the danceing was great even with a little thick fog hanging in the air. Lots of folks are getting ready for the BAHA cruse.

you may not need your engines running down hill--i didnt use mine much after ensenada, and only used it then as we were caught by the calm at salsipuedes, just north of ensenada. there should be plenty of wind and decent seas at this time of year.
downhill is EASY ... uphill is where the bash comes in. unless you get the headwinds that like to play with folks, no matter which direction ye head....

Between us there was, as I have already said somewhere, the bond of the sea. Besides holding our hearts together through long periods of separation, it had the effect of making us tolerant of each other's yarns -- and even convictions.Heart of DarknessJoseph Conrad

Be very careful out there... not much room for fun and playin' around. Don't mean to put a damper on the trip but it is serious business out there. A lot of planning, charting, decision making, meteorology and a bit of luck.
Play it conservatively and don't push it just to get to the next port.
Will be in Catalina in a couple of days, relaxing on a deliverycruise for a week... hoping for good weather and not too much of a head wind or head-on buck past San Clemente to Catalina... life is good south of Conception! Cheers, Capt Phil